The present disclosure relates to an exhaust air conduit for conducting away exhaust air from a pneumatically powered pump, in particular, from a coating agent pump in a painting plant.
In modern painting plants for painting motor vehicle bodywork components, pneumatically powered pumps are often used for pumping the paint to be applied. Such pneumatically powered pumps typically have a pneumatic cylinder and a piston which is displaceable in the pneumatic cylinder, and compressed air can be applied to the piston on both sides in order to displace the piston in the desired direction. Via a common piston rod, the piston in the pneumatic cylinder can deform, for example, two pumping diaphragms, as described in the German patent application DE 10 2013 003 620 B4. In such configurations, exhaust air from the pneumatic cylinder is typically controlled with a switch-over unit and is then discharged through a sound damper into the surroundings, with the sound damper is directly flange-mounted onto the switch-over unit.
It is disadvantageous in these known pumps that the exhaust air from the pneumatic cylinder is initially under pressure and then expands, which leads to intense cooling of the exhaust air. The cooling of the exhaust air can result in an undesirable formation of condensation, e.g. water collecting in the exhaust air conduit and, in particular, on the switch-over unit and the sound damper. It is possible that such expansion-induced cooling can, in some circumstances, freeze the condensation water and impairs the functional capability of the switch-over unit.
Additional examples of known pumps of this type are those disclosed in, for example, DE 44 25 515 A1 and U.S. Pat. No. 5,094,596.